Add folder anatomy (scripts/agent.py + references/api-reference.md) for 648 cybersecurity skills

Complete skill folder anatomy across all cybersecurity skills:
- scripts/agent.py: 80-150 line Python agents using real libraries (impacket,
  boto3, azure-mgmt-*, kubernetes, pefile, yara, scapy, shodan, stix2, etc.)
- references/api-reference.md: real API documentation with method signatures
- LICENSE: MIT license for all skill folders

skills/implementing-mtls-for-zero-trust-services/SKILL.md

@@ -0,0 +1,45 @@
+---
+name: implementing-mtls-for-zero-trust-services
+description: >
+  Configures mutual TLS (mTLS) authentication between microservices using Python
+  cryptography library for certificate generation and ssl module for TLS verification.
+  Validates certificate chains, checks expiration, and audits mTLS deployment status.
+  Use when implementing zero-trust service-to-service authentication.
+---
+
+# Implementing mTLS for Zero Trust Services
+
+## Instructions
+
+Generate CA certificates, issue service certificates, and configure mutual TLS
+verification for service-to-service authentication.
+
+```python
+from cryptography import x509
+from cryptography.x509.oid import NameOID
+from cryptography.hazmat.primitives import hashes, serialization
+from cryptography.hazmat.primitives.asymmetric import rsa
+import datetime
+
+# Generate CA key and certificate
+ca_key = rsa.generate_private_key(public_exponent=65537, key_size=4096)
+ca_cert = (x509.CertificateBuilder()
+    .subject_name(x509.Name([x509.NameAttribute(NameOID.COMMON_NAME, "Internal CA")]))
+    .issuer_name(x509.Name([x509.NameAttribute(NameOID.COMMON_NAME, "Internal CA")]))
+    .public_key(ca_key.public_key())
+    .serial_number(x509.random_serial_number())
+    .not_valid_before(datetime.datetime.utcnow())
+    .not_valid_after(datetime.datetime.utcnow() + datetime.timedelta(days=3650))
+    .add_extension(x509.BasicConstraints(ca=True, path_length=None), critical=True)
+    .sign(ca_key, hashes.SHA256()))
+```
+
+## Examples
+
+```python
+import ssl
+context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
+context.load_cert_chain("client.pem", "client-key.pem")
+context.load_verify_locations("ca.pem")
+context.verify_mode = ssl.CERT_REQUIRED
+```